The subject matter disclosed herein relates to dual evaporator refrigerator appliances, and more particularly to increasing energy efficiency in such a dual evaporator refrigerator appliance.
Many refrigerator appliances are based on a vapor-compression refrigeration technique. In such a refrigeration technique, a refrigerant serves as the medium that absorbs and removes heat from the space to be cooled, and transfers the heat elsewhere for rejection.
The evaporator is the part of the refrigeration system through which the refrigerant passes to absorb and remove the heat in the compartment being cooled (e.g., freezer compartment or fresh food compartment). Some refrigerator appliances are designed to have two separate evaporators, for example, one serving as an evaporator in a freezer compartment of the refrigerator (i.e., a freezer evaporator) and the other serving as an evaporator in a fresh food compartment of the refrigerator (i.e., a fresh food evaporator).
Dual evaporator refrigeration systems have certain advantages over single evaporator refrigeration systems. For example, many dual evaporator systems have separate refrigeration cycles for the freezer compartment and the fresh food compartment. Most dual evaporator systems have isolated airflow systems and thus the airflow in the refrigerator does not circulate between both compartments as it does in a single evaporator refrigeration system. Thus, by having an isolated airflow system in a dual evaporator system, odors that come from food stored in the fresh food compartment do not carry into the freezer compartment and then settle in ice cubes made in the freezer compartment causing unpleasant tastes when consuming the ice cubes.
However, most existing dual evaporator refrigeration systems are known to be costly and more complex than single evaporator refrigeration systems. Such existing dual evaporator refrigeration systems are also known to incur cycling losses when switching operation from the fresh food evaporator to the freezer evaporator. Still further, the evaporators in such existing systems are known to be relatively large. Such drawbacks negatively impact the energy efficiency of the appliance in which the refrigeration system resides.